The present invention relates to a device to retain a coiled or flexible member, and, more particularly, to a device for containing a length of optical fiber to allow the easy coiling and uncoiling of the optical fiber to the retention device and the device is adapted to be affixed to a planar surface such as a printed circuitboard.
There are currently in use various devices, such as spools and the like, that are used to contain a flexible member, including optical fibers, and such devices can be affixed to a printed circuitboard. Typically, such devices are used to retain a length of such optical fiber in a coil so that the fiber is available and to present a neat appearance by providing a coiling device to take up any excess fiber to keep it out of the way of other components associated with the printed circuitboard.
With the use of optical fiber it is preferred to have a quantity of the optical fiber on hand in such circuit boards for later use if additional fiber is needed as well as certain technical reasons, that is, an additional length of the optical fiber reduces the effect of an echo in the transmission of signals over that fiber.
One of the difficulties of the present fiber retention devices, however, is that they are normally quite cumbersome to wrap and to unwrap the optical fiber around the retaining device and, due to the close quarters in which such devices are used, it would be advantageous if there were an optical fiber retaining device that would enable the technician to easily wrap and unwrap the optical fiber with a minimum of intricate movements of the fiber, that is, a device where the technician can simply wrap and unwrap the optical fiber in a easy, straightforward manner.
As a further drawback of the present optical fiber retention devices, there is required a means of affixing the fiber retaining device to the printed circuitboard. With the use of printed circuitboards, however, the real estate on the board itself is very valuable so it is not at all desirable for the fiber retaining device to be affixed directly to the circuitboard so as to take up the real estate. Current means of affixing the fiber retention devices to a circuitboard include the use of screws that mate with screw holes provided in the circuitboard, adhesives that affix the fiber retaining device directly to the circuitboard and the use of tie wraps as well as other retaining devices. In all of the aforementioned current means of affixation, however, the method of affixation is relatively cumbersome and may require tools and the retention device takes up a considerable amount of that valuable real estate on the circuitboard itself, thus reducing the space available for the necessary electronic components on that circuitboard.
Thus, it would be advantageous to have a fiber retention device that would enable the easy coiling and uncoiling of the optical fiber within the device and which is easily affixed to a circuitboard without taking up the valuable real estate on that circuitboard
In accordance with the present invention, therefore, there is provided a optical fiber retention device that overcomes the difficulties and problems of the present prior art retention devices and which allows the coiling and uncoiling of the optical fiber with respect to the device. As used, the present invention will be described as specifically relating to the preferred environment, that of its use in the coiling and uncoiling of an optical fiber, however, as will be seen, the present invention can be used with other flexible members, including electrical wires.
The present optical fiber retaining device is made up of a relatively thin material, preferably of a plastic material but may be another material, such as metal or wood and which has one surface thereof coated with an adhesive material. That surface is preferably a flat, planar surface. The adhesive is selected such that an optical fiber can be affixed to the adhesive coated surface of the optical fiber retention device to securely retain the fiber to the adhesive surface, but which enables the removal of the optical fiber by simply exerting a small force to pull the optical fiber off of the adhesive coated surface.
Accordingly the optical fiber retention device includes a raised guide surface that extends outwardly from the surface on which the adhesive is coated, and the raised guide surface allows the optical fiber to be wrapped or coiled around that raised guide surface so as to provide a guide for the wrapping or coiling of the optical fiber and to insure that the optical fiber is properly and neatly coiled around the guide surface of the device. In the preferred embodiment, the raised guide surface is comprised of a pair of circular surfaces that are displaced with respect to each other, however, other configurations of raised guide surfaces can be used with the present device. Such other configuration can be circular, elliptical or other irregular shape.
In addition, the present optical fiber retention device is readily affixed to a surface, such as the surface of a printed circuitboard, by means of at least one, preferable a plurality, of tabs that can be extended outwardly in a direction rearwardly from the adhesive coated surface and which tab or tabs can be affixed to the surface of the printed circuitboard to retain the optical fiber retention device thereto. By making the length of the tabs to be at least a predetermined length, the planar coated surface of the optical fiber retention device is, after affixation, located a finite, predetermined distance away from the surface of the printed circuitboard, that is, the tabs act as standoffs so that the planar surface that is coated with the adhesive is displaced sufficiently away from the surface of the circuitboard so as to not take up any of the valuable real estate on that circuitboard. Thus, the tabs can be formed as integral with the planar surface of the fiber retention therefrom so as to minimize the costs of producing the optical fiber retention device and yet allow electronic components to be present on the printed circuitboard beneath the retention device.
As a further feature of the present invention, the outer ends of the tabs can be, themselves, formed as generally planer surfaces that are coated with an adhesive so that the outwardly extending ends of the tabs can simply be contacted to the surface of the printed circuitboard to secure the optical fiber retention device to the circuitboard, thus no tools or other affixation devices, such as screws, are needed to properly secure the present optical fiber retention device to a printed circuitboard. As an alternative, an adhesive can be applied to the generally planar surfaces of the tabs at the time the optical fiber retention device is affixed to a circuitboard.
As a still further feature of the present invention, the optical fiber retention device can be used, not only for the affixing of the coiled optical fiber to a printed circuitboard, but can be used for the shipping of the optical fiber in commerce, that is, the manufacturer of the optical fiber can initially coil the optical fiber onto a retention device constructed in accordance with the present invention and then ship that optical fiber in the form of the pre-coiled optical fiber already affixed to the retention device so that the customer need not uncoil the optical fiber from some form of reel of the manufacturer but can simply directly use the optical fiber as it is received to affix the fiber to a printed circuitboard.
Other features of the present optical fiber retention device will become apparent in light of the following detailed description of a preferred embodiment thereof and as illustrated in the accompanying drawings.